JAC Board Class 8th Social Science Solutions Geography Chapter 3 Mineral and Power Resources
JAC Class 8th Geography Mineral and Power Resources InText Questions and Answers
Page 25
Question 1.
Identify the Canadian Shield, the Appalachians, Western Cordilleras and Lake Superior with the help of an atlas.
Answer:
Students need to do it on their own.
Page 26
Question 2.
List uses of any five minerals.
Answer:
Uses of five minerals:
- Granite:
Used as a building stone such monuments, statues. Also used in highway construction and railway ballast. - Lead:
Used in television tubes and batteries. - Aluminum:
Used in manufacturing aeroplane and automobiles. It is also used in canning and bottling industries. - Copper:
Used in electric cables and wires, switches, coins and jewelry. - Gold:
Used for scientific and electronic instruments, computer circuitry, aerospace industry. Also used in jewelry, medicine and dentistry.
JAC Class 8th Geography Mineral and Power Resources Textbook Questions and Answers
Answer The Following Questions.
(i) Name any three common minerals used by you every day.
Answer:
Three common minerals used by us every day are iron, aluminum and copper.
(ii) What is an ore? Where are the ores of metallic minerals generally located?
Answer:
Ores are the minerals which are rich in a particular element and can be mined. The ores of metallic minerals are generally located in igneous and metamorphic rock formations.
(iii) Name two regions rich in natural gas resources.
Answer:
Two regions which are rich in natural gas resources are:
In the world Russia and Norway.
In India Krishna Godavari Delta and Jaisalmer.
(iv) Which sources of energy would you suggest for
Answer:
Sources of energy suggested for:
- Rural areas – Biogas and solar energy are feasible options.
- Coastal areas – Tidal energy and hydel energy are good options.
- Arid regions – Solar energy and wind energy are suitable options.
(a) rural areas
(b) coastal areas
(c) Arid regions
(v) Give five ways in which you can save energy at home.
Answer:
Five ways in which we can save energy at home are:
- For cooking fuel use of biogas would save energy.
- Misuse of electricity should be avoided such as switch off the lights and fans when not required.
- Solar energy must be used as much as we can.
- Energy efficient devices should be used such as LED bulbs and tubes.
- While cooking using energy efficiently such as covering with lid, pressure cook, etc.
Tick the correct answer.
Question 2.
(i) Which one of the following is NOT a characteristic of minerals?
(a) They are created by natural processes.
(b) They have a definite chemical composition.
(c) They are inexhaustible.
(d) Their distribution is uneven.
Answer:
(c) They are inexhaustible.
(ii) Which one of the following is a leading producer of copper in the world?
(a) Bolivia
(b) Ghana
(c) Chile
(d) Zimbabwe
Answer:
(c) Chile
(iii) Which one of the following practices will NOT conserve LPG in your kitchen?
(a) Soaking the dal for some time before cooking it.
(b) Cooking food in a pressure cooker.
(c) Keeping the vegetables chopped before lighting the gas for cooking.
(d) Cooking food in an open pan kept on low flame.
Answer:
(d) Cooking food in an open pan kept on low flame.
Question 3.
Give reasons.
- Environmental aspects must be carefully looked into before building huge dams.
- Most industries are concentrated around coal mines.
- Petroleum is referred to as “black gold”.
- Quarrying can become a major environmental concern.
Answer:
- Environmental aspects must be carefully looked into before building huge dams because it can create imbalance and deforestation may happen. Humans, wild animals become displaced.
- Most industries are concentrated around coal mines because it ensures the availability of fuel and transportation costs get reduced.
- Petroleum is referred to as “black gold” because in the crude form it is in black colour and its derivatives are extremely valuable such as petroleum. Different products of petroleum are used in are day to day life such as petrol, diesel, kerosene.
- Quarrying can become a major environmental concern because pits are not covered so they may cause environmental threats after quarrying.
Question 4.
Distinguish between the followings.
- Conventional and
- Biogas and natural gas
- Ferrous and nonferrous minerals
- Metallic and nonmetallic minerals
1.
| Conventional Sources of energy | Non-conventional N Sources of energy |
| From long time they have been used. | These sources have been identified in recent past. |
| These are mostly polluting. | These are non-polluting |
| Firewood, coal are the examples. | Wind energy, solar energy, tidal energy are the examples. |
2.
| Biogas | Natural Gas |
| It is a non- conventional source of energy. | It is a conventional source of energy. |
| It is a renewable source. | It is a non-renewable source. |
| It is obtained from the decaying of the organic waste. | It is a by-product which is obtained from the extraction of petroleum. |
3.
| Ferrous Minerals | Non-ferrous N minerals |
| Minerals which contain iron are Ferrous minerals. | Minerals which do not contain iron are Non- ferrous minerals. |
| Iron ore is a ferrous mineral. | Limestone is a non- ferrous mineral. |
| These are magnetic in nature. | These are non-magnetic in nature. |
| India has abundant of ferrous minerals. | India is deficient of non-ferrous mineralsv |
4.
| Metallic Minerals | Non-metallic Minerals |
| In raw form, metals are found. | It does not contain metals. |
| New products can be obtained by melting them. | On melting, they do not give new products. |
| These are associated with igneous rocks. | These are associated with sedimentary rocks. |
| Bauxite is a metallic mineral. | Gypsum is a non-metallic mineral. |
Question 5.
Activity
- Use pictures from old magazines to show different kinds of fuels used by us in our lives and display them on your bulletin board.
- Design a poster highlighting energy conservation tips you would take for your school.
- Salma’s class took up an action campaign to do an energy audit of their school by surveying electricity consumption. They prepared survey sheets for the students of the school.
Answer:
Students need to do it on their own.
JAC Class 8th Geography Mineral and Power Resources Important Questions and Answers
Multiple Choice Questions
Question 1.
Minerals are
(a) naturally occurring substances that have definite chemical compositions.
(b) artificially made substances that have a definite chemical compositions.
(c) human made substances that have definite chemical compositions.
(d) liquids and gases that are found everywhere.
Answer:
(a) naturally occurring substances that have definite chemical compositions.
Question 2.
Physical properties of minerals are
(a) population and economy.
(b) pollution and political factors.
(c) colour, density, hardness, and chemical properties such as solubility.
(d) weather and plant action.
Answer:
(c) colour, density, hardness, and chemical properties such as solubility.
Question 3.
The process of simply digging out minerals such as lead and coal that lie near the surface of the earth is called.
(a) drilling
(b) quarrying
(c) open cast mining
(d) none of these
Answer:
(b) quarrying
Question 4.
The colour of a rock if it contains a large amount of copper is.
(a) green
(b) quarrying
(c) silver
(d) red
Answer:
(b) quarrying
Question 5.
The world’s leading tin producers are:
(a) India, Pakistan, and Afghanistan
(b) India, China, and USA
(c) China, USA, and Austral
(d) China, Malaysia, and Indonesia
Answer:
(d) China, Malaysia, and Indonesia
Question 6.
Aluminum, obtained from its ore bauxite is used in.
(a) automobiles
(b) buildings
(c) airplanes
(d) all of these
Answer:
(d) all of these
Question 7.
The ways to conserve minerals so that they may also be available to future generations are
(a) reuse, reduce use, and recycle.
(b) reuse and recycle.
(c) reduce use and recycle.
(d) none of these
Answer:
(a) reuse, reduce use, and recycle.
Question 8.
The disadvantages of using firewood as a fuel are:
(a) It is polluting and promotes the greenhouse effect.
(b) It takes time to collect.
(c) It results in deforestation.
(d) All of these
Answer:
(a) It is polluting and promotes the greenhouse effect.
Question 9.
Natural gas is usually found with deposits of .
(a) firewood
(b) iron ore
(c) petroleum
(d) coal
Answer:
(c) petroleum
Question 10.
The main parts in a hydro-electric power station:
(a) a generator, a turbine, and a motor
(b) a water reservoir, a turbine, and a motor
(c) a generator, a rocket, and a turbine
(d) a water reservoir, a turbine, and a generator
Answer:
(d) a water reservoir, a turbine, and a generator
Very Short Answer Type Questions
Question 1.
How many types of minerals have been identified and how many are considered as ore minerals?
Answer:
There are around 2,800 types of minerals which have been identified and only about 100 are considered ore minerals.
Question 2.
Which country has no minerals?
Answer:
Switzerland has no known minerals.
Question 3.
Which country is the largest producer of bauxite in the world?
Answer:
Australia is the largest producer of bauxite in the world.
Question 4.
What are the two naturally occurring radioactive elements?
Answer:
Uranium and Thorium are the two naturally occurring radioactive elements.
Question 5.
Which is the most abundantly found fossil fuel?
Answer:
The most abundantly found fossil fuel is coal.
Question 6.
In which place of India has huge tidal mill farms?
Answer:
Gulf of Kachchh in India has huge tidal mill farms.
Question 7.
Name the first country to develop hydroelectricity in the world.
Answer:
Norway was the first country in the world to develop hydroelectricity in the world.
Question 8.
Name two areas in Australia which have large deposits of gold.
Answer:
Kalgoorlie and Coolgardie areas of western Australia have the largest deposits of gold.
Question 9.
Where is the site of the world’s first solar and wind powered bus shelter?
Answer:
The site of the world’s first solar and wind powered bus shelter is in Scotland.
Question 10.
Name the places where the geothermal power plants located in India.
Answer:
In India, geothermal plants are located in Manikaran in Himachal Pradesh and Puga Valley in Ladakh.
Short Answer Type Questions
Question 1.
CNG is considered an eco-friendly fuel. Why?
Answer:
Compressed natural gas (CNG) is a popular eco-friendly fuel because it causes less pollution than petroleum and diesel.
Question 2.
Give one advantage and one disadvantage of geothermal energy.
Answer:
Advantage – Clean, eco-friendly and always available. Disadvantages – Located far away from cities and so costly to transport the electricity.
Question 3.
What are the main types of power resources?
Answer:
The main types of power resources are conventional and non-conventional resources.
Question 4.
Explain in brief the mineral salt?
Answer:
The mineral salt is obtained from seas, lakes and rocks. India is one of the world’s leading producers and exporters of salt.
Question 5.
Coal is known as “buried sunshine”. Why?
Answer:
Coal is known as “Buried Sunshine” because the coal which we are using today was formed millions of years ago when giant ferns and swamps got buried under the layers of earth.
Question 6.
“All minerals are rocks but all rocks are not minerals”. Justify in brief.
Answer:
All minerals are rocks but all rocks are not minerals because more than 2,800 types of minerals have been identified but only about 100 are considered ore minerals which can be used.
Question 7.
Minerals are considered non. renewable. Why?
Answer:
Minerals are a non-renewable resource because it takes thousands of years for the formation. The rate of formation is much smaller than the rate at which the humans consume these minerals.
Question 8.
How do we get nuclear energy?
Answer:
We get nuclear power from energy stored in the nuclei of atoms of naturally occurring radioactive elements like uranium and thorium. These fuels undergo nuclear fission in nuclear reactors and emit power.
Question 9.
What are the nuclear power stations in India.
Answer:
The nuclear power stations in India are located in Kalpakkam in Tamil Nadu, Tarapur in Maharastra, Ranapratap Sagar near Kota in Rajasthan, Narora in Uttar Pradesh and Kaiga in Karnataka.
Question 10.
Distinguish between a rock and an ore.
Answer:
Difference between a rock and an ore:
| A rock | Ail ore |
| A rock is an aggregate of one or more minerals but without definite and fixed composition of constituent of mineral. | Rocks from which minerals are mined are called ores. |
Long Answer Type Questions
Question 1.
What are the advantages and disadvantages of
(a) Coal
(b) Crude oil
Answer:
(a) Coal
Advantages
- It is extensively available.
- It is efficient to convert to electricity.
- It offers a low capita investment.
- It is a full time energy resource.
Disadvantages
- It is a source of pollution.
- It is bulky to transport.
- It is not a renewable resource.
- It creates high level of radiation.
- Clean coal also has high level of methane.
(b) Crude oil Advantages
- It is easier to transport such as tankers are used.
- It is the basis of petro-chemical industry.
- It can be extracted easily.
- It is a powerful source of energy. Disadvantages
- Depletion of oxygen due to oil spillage.
- Pollutants released caused acid rain.
- Exploration of new fuel is not easy.
- It is a non-renewable source.
Question 2.
Briefly explain the method of extraction.
Answer:
The method of extraction consists of mining, drilling and quarrying.
(i) Mining:
The process of taking out minerals from rocks which are buried under the earth’s surface is called mining. Open-cast mining Minerals that lie at shallow depths are taken out by removing the surface layer, this is known as open-cast mining.
Shaft mining :
Deep bores called shafts have to be made to reach mineral deposits that lie at great depths. This is known as shaft mining.
(ii) Drilling:
Petroleum and natural gas occur far below the earth’s surface. Deep wells are bored to take them out. This process is known as drilling.
(iii) Question uarrying :
Minerals that lie near the surface are simply dug out, by the process known as quarrying.